Apparatus for impregnating thread



E. F. GALLAUDET 2,363,783 APPARATUS FOR IMPREGNATING' THREAD Nov. 28, 1944.

Filed June l4, 1941 INVENTOR v lLsa/vEGq44Az/0Er BY H g -1M,

7 ATTO NEYs Patented Nov. 28, 1944 UNITED STATES PATENT OFFICE 2,363,783 a armm'rus ron mimena'rmo THREAD Edson F. Gallaudet, Pine Orchard, Conn. Application June 14, 1941, Serial No. 398,050

9 Claims.

The present invention relates to apparatus for using thermoplastic material in the manufacture of filled and coated cords, and embodies, more specifically, an improvement or modification in the apparatus described in my U. S.- Patent No. 1,974,453, dated September 25, 1934.

The invention has to do particularly with the manufacture of filled or coated cords for use in tennis racquets and the like, wherein silk or other fibrous strands are impregnated with a suitable material to impart strength; life and suitable physical properties to the finished cord.

In accordance withthe present invention, it is proposed to provide an apparatus by means of which filled or coated cords may be manufactured having properties including greater strength and wear resistance than similar cords that are now available.

A further object of the invention is to provide an improved apparatus of the above character wherein thermoplastic materials may be utilized for filling or coating cords at elevated temperatures, the setting or'hardening of the materials occurring as the filled and coated cord cools 01f.

Yet another object of the invention is to provide an improved apparatus of the above character wherein the filling or coating operation may be accomplished while effectively removing excess quantities of the thermoplastic material that may result from drawingthe mass of filled or coated strands to the desired size.

A further object of the invention is to provide an apparatus for filling or coating strands in the manner above referred to, wherein effective mechanism is provided for maintainingpredetermined temperature characteristics throughout the period of operation of the mechanism.

Yet another object of the invention is to provide a device of the above character wherein means are provided for drawin the filled or coated strands through a former which provides for the accurate forming of the filled strands to the desired size, while, at the same time, being sufficiently yielding to permit the passage of knots therethrough.

Further objects and advantages of the invention will be apparent as it is described in greater detail in connection with th accompanying drawing, wherein;

Fig. 1 is a view in section taken on a planepassing through the axis of a device constructed in accordance with the present invention.

Fig. 2 is an enlarged view, partly broken away and in section, showing the upper nozzle of the a plane --5 of Fig. 1 and device having the improved characteristics of the present invention.

Fig. 3 is a partial view'in section, showing the drawing mechanism and taken on the line 3-3 of Fig. 2. i 1

Fig. 4 is a-view similar to Fig. 3, taken on the line 4-4 of Fig. 2.

Fig. 5 is a partial view in section, taken on the looking in the direction of the arrows. 7

Referring to the above drawing, a device is illustratedby means of which the present invention may be accomplished. This device consists of an upper casing l and a lower casing 2, that are secured in position by means of an assembly plate 3 having upper and lower threaded flanges 4 and 5, respectively. The upper and lower casings are threaded upon these respectiv flanges as illustrated in Figs. 1 and '5, in order that the device may be assembled in operating position.

The upper casing I thus forms a chamber 6 within which a nozzle 1 is adapted to be received, and also serves as a discharge chamber by means of which excess filling and coating material, a well as solventand other gases, may be discharged.

. An important part of my invention resides in the structure of th nozzle 1, and its coaction with the casing I by means of which the nozzle may serve to draw the mass of filaments to the desired diameter but, at the same time, be susceptibl of distention to accommodate enlargements such as knots in the filaments or strands. In order to accomplish this, the nozzle 1 isformed in three pieces in the following manner. A piece of half round carbon steel is planed down so that it has two flat faces intersecting along the axis of the cylindrical surface and lying in planes forming an angle of Three pieces of this bar, each about three inches long, are positioned so that their cylindrical surfaces form a complete cylinder and the assembly is soldered together. The assembly is thenbored out and turned down to form the pieces 'I-a, 1-5 and 1c. At their lower extremity, the pieces are flanged at 'l-d and threaded. at 'l-e so that the. assembly may be positioned in the plate 3 as illustrated in Figs. 1 and 5.

After being completely machined, the three identical parts are then heated and separated and the solder removed therefrom. Each piece is then bent slightly so that its tip curves approximately of an inchin the direction of its own axis. They are then tempered, clamped together and screwed and threaded into the assembly Dlate 3.

The foregoing construction results in a nozzle order that excess the desired size the filled and coated threads twisted together to form the finished cord and yet sufliciently yielding to accommodate a knot by distending in a manner which will be readily apparent. In this connection, the top inner surface l-a ofthe casing l is formed on a radius which is the same as that of the are described by the tips of the elements 1-11, 1-17 and 1-0, as they extend to accommodate a knot. The orifice '|j of the nozzle lies beneath an enlarged aperture i-b formed in the casing I, and, in this fashion, a reasonably tight connection is normally maintained between the end of the nozzle 1 and the upper wall of the casing l. Upon distention of the nozzle I when a knot passes through it, sure within the chamber 8 will escape but this will not impair the operation of the mechanism.

Each of the three elements l--a, '|--b and '|-c is formed with an upper aperture 8 and a lower aperture 9 as illustrated in Figs. 1, 2, 3 and 4, in filling or coating material and solvent may escape from the interior of the nozzle. Such material collects in a sump 3-a to be discharged into a discharge conduit 3-b, mounted in the plate 3. Cups Ill-and H may extend into the chamber and be threaded into the top wall of the casing l in order to receive a ther-' mometer and a thermostat, should such instruments be required during the operation of the device.

The lower portion of the casing, 2 carries a bottom .plate l2 formed with a threaded flange i2--a to enable the casing to be secured thereto. A chamber I3 is thus formed within the bottom casing 2 in order that the device may be heated. To accomplish this, a steam fitting I4 is secured to the plate 3, the plate being bored at ld-a to permit the steam to be introduced into the bottom chamber IS. A discharge conduit l5-is carried by the bottom plate l2, the conduit communicating with the chamber 13 and with a pressure regulating valve and trap indicated generally at lS-a.

In this fashion, a desired steam pressure may be maintained in the chamber I3 andthe heating accomplished efiectively.

In order that the solvent and excess material a certain amount of air under presand material are directed through and twisted together in a treating chamber formed as a tube 2| positioned in the axis of the chamber 2 and threaded'into a cylindrical flange 22 formed in the plate 3. The tube 2| is slidably received in the bottom plate 12, positioned by means of a threaded flange 23, and'packed by a gland 24. The lower extremity of the tube 2| receives a lower nozzle 25 which may accomplish a preliminary drawing or uniting of the threads and filling material. In passing-through the tube 2| the threads and material are twisted together and heated sufllciently to melt the material and prepare the twisted mass of threads for the drawing operation accomplished by the nozzle 1. As the material is picked up in liquid form from the vat 20, the heat applied thereto in the tube 2| will vaporize the solvent which will then escape through the apertures 8 into the chamber 8. Any excess material drawn off of the cord by the nozzle I will escape through the apertures 8 and fall into the sump 3-11. The air under pressure in the chamber 6 will then effectively discharge the material through the fitting 3b.

In practice, it has been found that effective.

results are accomplished by maintaining the temperature conditions in the treating and forming device between 250 and 300 F. For example, steam may be utilized in the chamber :3 at a pressureof about 35 pounds and a temperature of about 280 F. The orifice of the lower nozzle 25 is preferably about 25% greater in diameter than the orifice of the upper nozzle 1, and, if desired, the entire assembly may be supported by the lower nozzle 25, as illustrated.

If desired, the chamber l3 may be heated electrically instead of by steam, in which event-suitable resistance elements are placed therein and controlled thermostatically.

While the invention has been described with escaping from the nozzle 1 may be effectively discharged from the chamber 6, air under pres sure is supplied through a fitting it that is secured to the plate 3. The plate is bored at HM in order that communication may be established between the fitting i6 and a tube ll that is secured, at One end, to the plate 3 to extend downwardly and then upwardly to form a coil ll. The upper end of the coil is secured to the plate 3 and communicates with a vent tube I8 that opens into the chamber 6.

Heated air is thus maintained within the chamber 6 under pressure in order that all excess material may be removed therefrom effectively.

In order that the cord may be suitably filled and coated, its component threads are treated with a thermoplastic material. This treating may be accomplished either by drawing the threads I9 through a supply of a solution of the material contained in a rotating vat 20, or the material may bebrought to the cord in continuous strands I9-a, a small number of thermoplastic fibers being combined with strength fibers forming each strength thread, or a small number reference to the specific drawing above referred to, it is not to be limited save as defined in the appended claims.

I claim:

1. Means for filling and coating cord formed of a plurality of threads comprising a casing forming a chamber, means to move through the chamber high strength threads impregnated with filling material and twisted together, means to heat the chamber, a nozzle having an orifice through which the impregnated and twisted threads are drawn from the heating chamber to form the cord in a desired fashion, an upper casing surrounding the nozzle and forming an upper chamber thereabout, a material outlet in the lower portion-of the upper chamber, and means to introduce a fluid under pressure into the upper chamber to remove excess material therefrom.

2. Means for filling and coating cord formed .of a plurality of threadscomprising a casing forming a chamber, means to move through the chamber high strength threads impregnated with filling material and twisted together, means to heat the chamber, a nozzle in a wall of said chamber having an orifice through which the impregnated and twisted threads are drawn from the heating chamber to form the cord in a desired fashion, an aperture in the nozzle through which excess material may escape, a second aperture in the nozzle through which gas may be discharged, and means to remove the said excess material from around said nozzle.

3. Means for filling and coating cord formed of a plurality of threads comprising upper and lower casings forming i 'espectively upper and lower chambers, means to. move through the chambers high strength threads impregnated with filling material and twisted together, heating meansin the lower chamber, 'a nozzle in the upper chamber having an orifice through which the impregnated and twisted threads are drawn to form the cord in a desired fashion and having another aperture to allow' the escape of excess material, said nozzle being formed of a plurality of engaging, relatively yieldable sections to per mit the passage of knots therethrough, and said nozzle and uppercasing beingformed to maintain a substantially fluid tight connection there between. l

4. Means for filling and coating cord formed of a plurality of threads comprising upper and lower casings forming respectively upper and lower chambers, means to move through the chambers high strengthgthreads impregnated with filling material and twistedto'gether, a nozformed'of a plurality of tightly engaging, relatively yieldable sections to permit the passage of knots therethrough, and said nozzle and upper casing being formed to maintain a substantially fluid tight connection therebetween, means to supply fluid under pressure to the upper chamber,

meansto discharge excess material from the upper chamber by'the said fluid, and heating means in the lower chamber.

5. Means for filling and coating cord formed of a plurality of threads comprising upper and lower casings forming respectively upper and lower chambers, means to move through the chambers high strength threads impregnated with filling material and twisted together, a nozzle in the upper chamber having an orifice through which the impregnated and twisted threads are drawn to form the cord in a desired fashion and having another aperture to permit the escape of excess material, said nozzle being formed of a plurality of tightly engaging, relatively yieldable sections to permit the passage of knots therethrough, and said nozzle and upper casing being formed to maintaina substantially fluid tight connection therebetween, means to and threads and the fluid.

., supply fiuid under pressure to the upper chamber,

means to discharge excess material from the upper chamber by the saidifluid and common meansin the lower chamber to heat the material 6. A nozzle-through which a treated cord is adapted to be drawn comprising a base portion adapted to be mounted in a support, a portion taperingto an orifice, said tapering portion being formed of a pluralityof sections having tightly engaging edges extending longitudinally of saidtapering portion, and a plurality of apertures extending through the sides of said tapering portion. 7

'7. A nozzle through which a treated cord is,

- adapted to be drawn comprising'a base portion adapted to be mounted inna support, a portion tapering to an orifice, said ta'peringportion beingformed of a plurality of sections taperingto extremities which form the said orifice, said sections having tightly engaging edges extending longitudinally of said tapering'portion-the said section.

extremities being bent inwardly toward the nozzle axis, and an aperture 8. A nozzle through which a'treated cord is adapted to be drawn comprising a base portion adapted to be mounted in a support, a portion tapering to an orifice, said tapering portion being formed of a plurality of sections tapering to extremities which form the said orifice, said set:-

- tions having tightly engaging edges extending longitudinally of said taperingportion the said extremities being bent, inwardly toward the nOZf zle axis, and a plurality of apertures extending through each section spaced axially'of the nozzle. 9. Means for filling and coating cord 'formed of a plurality of twisted'threads impregnated with filling material comprising a. casing forming a chamber, a'nozzle in the wall of and within said chamber having an orifice through which the threads are drawn to form the cord, another aperture in a side of said nozzle through which excess filling material escapes into the chamber, and means to supply fluid under pressure: to force said excess: material from said chamber. 1 EDSQN F. GAILAUDET.

extending through each, 

